How are the constellations in the universe divided? In the universe, how to specify coordinates?

It was the ancient wise men who tried to distinguish and know every star. So the sky is divided into several regions, and the pattern of the brightest stars in each region is called constellation.

The stars in the whole area are named after this constellation. For example, Sagittarius A is a bright main star of Sagittarius, and Sagittarius a- 1 is a satellite next to a bright main star of Sagittarius.

Dividing constellations is the need to facilitate astronomical research.

Cosmic coordinates are the same as the longitude and latitude lines of the earth.

Imagine the sky around us as a curved surface, and we are in the center of this celestial sphere. We apply the longitude and latitude lines to this celestial sphere, and the position of each star's projection on the celestial sphere is the coordinates of this star. We can find this star by reading the position on the earth.

This is also to facilitate the needs of astronomical research.

But it is more scientific than constellation division.